Abstract: Objective To evaluate the efficacy and safety of erlotinib on the advanced adenocarcinoma of non small cell lung cancer(NSCLC) patients after failure of gefitinib treatment and study the relationship between efficacy and clinical characteristics. Methods A retrospective analysis of advanced NSCLC patients who were previously treated with gefitinib and showed progression from June 2008 to February 2009. And the patients received erlotinib 150 mg/d until disease progression or the drug became intolerable because of toxicity. The efficacy, side effects and the relationship between efficacy and the epidermal growth factor receptor (EGFR) Tyrosine kinase inhibitors (TKi)s and clinical characters were observed. Results A total of 22 NSCLC patients were enrolled in this study. Among 22 patients, two had partial response and seven had a stable disease, resulting in an Objective response rate of 9%, and a disease control rate of 40.9%. The overall survival of those who had no benefit vs. those who had benefit were 82 days and 192 days respectively. The patients who had obtained disease control with erlotinib, showed a longer time to progress (TTP) (112 vs. 45.5 days, P<0.05). The most common toxic effects were skin rash and diarrhea. Conclusion Erlotinib seems to be effective in patients with advanced NSCLC after failure of gefitinib, especially in those who had benefit from prior gefitinib treatment.

Key words: erlotinib, gefitinib, non small cell lung cancer(NSCLC), adenocarcinoma